Sayyiduna Abu Hurayrah (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) "forbade selling grain until the two sa's have been applied to it. The excess and the shortfall are the seller's."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10701
Hadith Gradingمحدثین:حسن لغيره
Hadith Takhrij«حسن لغيره۔ اخرجه ابزار كما في نصب الرواية 4414»